1. Field of the Invention
The present invention relates to a fishing reel which incorporates therein a one-way clutch to thereby be able to have a reversal preventive function to prevent the reversal of a rotary drive shaft and, in particular, to a fishing reel which is improved in a one-way clutch mounting structure for mounting a one-way clutch onto the main body thereof.
2. Description of the Related Art
Conventionally, in a fishing reel, there is incorporated a reversal preventive device which is used to prevent the reversed rotation of a drive shaft rotatable in linking with the operation of a handle. As the reversal preventive device, in Japanese Utility Model Unexamined Publications Nos. Hei. 7-13161, Hei. 7-18568, Hei. 6-5467 and the like, there is disclosed a structure which employs a one-way clutch of a rolling type in order to reduce the degree of play for reversal of a drive shaft during a fishing operation to thereby improve the reliability of a hooking operation.
Referring to the structure for mounting the one-way clutch onto the reel main body in the fishing reels respectively disclosed in Japanese Utility Model Unexamined Publications Nos. Hei. 7-13161 and Hei. 7-18568, the outer periphery of an outer race forming a part of the one-way clutch is formed such that the cross section thereof has a non-circular shape, the inner periphery of a support portion forming a part of the reel main body, into which the one-way clutch outer race is to be fitted, is also formed such that the cross section thereof has the same shape as the outer race outer periphery, that is, a non-circular shape, and, by fitting the outer race into the support portion inner periphery, the one-way clutch can be fitted into the support portion of the reel main body in such a manner that the one-way clutch is prevented against rotation. However, in this mounting structure of a rotation preventive fitting type, in order to be able to achieve strong mounting with no play between the outer periphery of the one-way clutch outer race and the inner periphery of the reel main body support portion respectively formed in non-circular shapes while securing their concentricity with respect to the drive shaft, the non-circular-shaped portions of the outer periphery of the outer race of the one-way clutch and the inner periphery of the support portion of the reel main body must be worked with high precision respectively. In fact, however, such high-precision working is not only difficult to realize but also is the cause of the expensive products. Also, the fitted portions of the one-way clutch and reel main body are actually easy to loosen, which makes it difficult to obtain a reversal preventive function capable of reducing the degree of play for reversal due to the wedge action of the one-way clutch of a rolling type.
In more particular, if the outer race of the one-way clutch is fitted into the support portion of the reel main body with strong pressure, then the mutually fitting outer and inner peripheral surfaces of the on-way clutch outer race and reel main body support portion are deformed in an abnormal manner because they are both non-circular in section. Also, if there exists a working error between the mutually fitting portions, then the stronger the fitting pressure is, the more greatly the mutually fitting portions become eccentric following the working error, with the result that the center of the one-way clutch to be assembled to the support portion of the reel main body is caused to shift out of position and thus the concentricity of the one-way clutch with respect to the drive shaft can be impaired easily. This raises some problems: for example, the rotation of the drive shaft is made heavy, the wedge action of the one-way clutch is impaired, and the like. Conventionally, in most cases, the reel main body is formed of resin for the purpose of light weight. In this case, however, since the fitting receive portion of the resin reel main body is soft, the fitting portion thereof can be deformed or worn due to strong loads or shocks given in the reversal preventing operation, that is, the fitting portion can be loosened to thereby cause the reversal preventive device to operate in failure. If the outer race and the like of the one-way clutch are increased in diameter in order to reinforce the rotation preventive fitting portion thereof, then the fishing reel is also unfavorably increased in size as a whole.
On the other hand, in the fishing reel disclosed in Japanese Utility Model Unexamined Publication No. Hei. 6-5467, in order to improve the fitting precision of the one-way clutch with respect to the reel main body, while the outer periphery of the outer race of the one-way clutch is so formed as to have a circular cross section, a securing portion, which is composed of a projecting portion and a recessed portion formed on the end face of the outer race of the one-way clutch, is engaged with a securing portion receive portion formed on the end face of the reel main body, thereby providing an outer race rotation preventive function. In this structure, although an improvement in the concentricity precision of the one-way clutch of a rolling type with respect to the reel main body can be expected, in the reversal preventing operation, strong loads and shocks are directly given to the securing portion composed of the projecting portion and recessed portion formed on the end face of the outer race of the one-way clutch. For this reason, the secured or engaged portions of the one-way clutch and reel main body can be easily deformed, broken or worn, so that they are loosened with respect to each other, that is, play is generated between them soon. As a result of this, it is difficult to obtain a reversal preventive function which is capable of reducing the degree of play for reversal due to the wedge action of the one-way clutch of a rolling type. In this case, especially when the reel main body is formed of resin for the purpose of light weight, because the secured or engagement portion thereof is soft, the deformation or wear of such engaged portion is greater, thereby raising a fear that the reversal preventive device can fail to operate in a considerably early stage. Also, if the parts of the one-way clutch are increased in diameter in order to reinforce the rotation preventive securing portion thereof, then the fishing reel is also unfavorably increased in size as a whole.